Abstract: 【OBJECTIVE】Study on the Relationship between the Nitrogen Assimilation ,Transfer and Utilization of Different organs and Nitrogen use efficiency during grain filling in Different Genotypes Rice.【METHOD】The relationships between the nitrogen content, accumulation, distribution and utilization of different organs and nitrogen use efficiency by using ten different genotypes rice varieties were analyzed【RESULTS】The results indicated that during grain-filling the N-content of ear was not significantly different among types, and was significantly different among types in N-content of leaf and sheath and stem during the late grain-filling .The increase of the N-accumulation of ear was usually accompanied by decrease of N-accumulation of leaf and sheath , stems especially leaf and sheath ,and increase of the N-distribution ratio of ear was usually accompanied by decrease of N-distribution ratio of leaf and sheath during the grain filling. N-accumulation and distribution of ear, leaf and sheath, stem was significantly different among types at late grain-filling stage, and nitrogen use efficiency was significantly different among types during the grain-filling. N-use efficiency at mature stage were significant- negatively correlated with N-content of ear, leaf and sheath, N-accumulation and N- distribution ratio of leaf and sheath at late grain-filling stage and were significant-positively correlated with N- distribution ratio of ear at late grain-filling stage.【CONCLUSION】Which indicates that selection for combining with organ nitrogen can availably advance the select effect at rice high nitrogen use efficiency breeding